Open

At the end of the Saehan Sangsa / Zemina alliance, Kim Eulsuk formed his own independent development studio, employing several former Zemina programmers and freelancers like Koo Eunjoong, Lee Sanghun, Lee Kyuhwan and Lee Sangyoun (although the latter two didn't stay with the company for long). A year later, they became a second party developer for Daou Infosys, a partnership that produced more 8-bit console games than anyone else at the time. Other products were cheat modules for the Mega Drive and Super Famicom (the former was also capable of transferring data between the console and a PC).
In late 1993 Open announced their merger with the PC developer Namu, who were then working on three games, but in the end, none of those saw the light of day. Two years after the failed Daou-Innovation deal, a bunch of Open games actually made it to new shores. Another distributor of unofficial video game carts, HES, released a cartridge called 4 Pak All Action in 1995, which contained four games by the Korean developer. It is believed that only 5000 carts were produced.
Mega Drive developments were planned as well, but after Daou Infosys stopped investing in the console business, Open went with the tide and moved their efforts completely towards the PC.
Key People:
Kim Eulsuk: President
Koo Eunjoong: Director, Programmer
Lee Sanghun: Director, Programmer
Source: http://www.hardcoregaming101.net/korea/part1/company-open.htm